A conventional mechanical type brake actuator, which is used for a drum brake device, is comprised of, as main elements, a plate-like brake lever, a strut pivotally retaining the brake lever therein, and a pivot pin. The mechanical type brake actuator is positioned between a pair of brake shoes and the brake lever rotates relative to the strut with a pivot point therebetween as a fulcrum by pulling a brake cable connected to the brake lever so that a brake shoe engagement portion of the brake lever and a brake shoe engagement portion of the strut spread in an opposite direction to extend a distance therebetween, thereby operating the drum brake.
A conventional mechanical type brake actuator is so configured that a first connecting-hole, which is formed on the brake lever at a free end thereof positioned away from a pivoting portion (proximal portion) thereof, and a second connecting-hole, which is formed on a cable end fixed at an end of the brake cable, are aligned at a certain position where both connecting-holes are not obstructed with the strut at a cable releasing direction side, so that the connecting-pin can be inserted through both connecting-holes, thereby establishing the connection between the brake lever and the cable end. Thereafter, the brake cable is pulled, thus constantly positioning the connecting-pin within a space formed between a pair of facing plates to prevent disengagement of the connecting-pin from the brake lever.
Patent Document 1 (Japanese Unexamined Patent Publication No. 2001-349360) or Patent Document 2 (Japanese Unexamined Patent Publication No. 2004-293643) discloses one example of configurations where the connecting-pin is positioned within the space formed between the pair of facing plates to restrict the brake lever rotation in the cable releasing direction. These conventional inventions are technologies to prevent the connecting-pin from moving to a position where the connecting-pin can be disengaged from the brake lever by a clip that is attached on the strut. The brake lever and the brake cable are connected via the connecting-pin, and thereafter the clip is rotated to complete the connecting operation between the brake lever and the brake cable. After completion of the connecting operation between the brake lever and the brake cable, an attempt to rotate the brake lever in the cable releasing direction can be prevented because the clip restricts the brake lever rotation thereby preventing the disengagement of the connecting-pin from the brake lever. In addition, Patent Document 3 (Japanese Unexamined Patent Publication No. 2007-87195) discloses the invention that is a technology for restricting the connecting-pin movement. The present invention uses a clip with a by-pass hole to be installed on the strut to prevent the disengagement of the connecting-pin from the brake lever, and the connecting-pin is inserted through the by-pass hole of the clip, temporarily set on a first facing plate and the notched groove of the first facing plate, so that the brake lever and the brake cable are connected, and thereafter the clip is pressed with a thumb or a finger in a cable operating direction until a flat surface of the clip obstructs the notched groove of the first facing plate, thereby completing the connection between the brake lever and the brake cable. After completing the connecting operation, the invention is configured to prevent the disengagement of the connecting-pin from the brake lever by restricting the connecting-pin movement between the second facing plate without the notched groove and the flat surface of the clip.    [Patent Document 1] Japanese Unexamined Patent Publication No. 2001-349360    [Patent Document 2] Japanese Unexamined Patent Publication No. 2004-293643    [Patent Document 3] Japanese Unexamined Patent Publication No. 2007-187195
The above-described conventional mechanical type brake actuator has the following problems.
<1> In order to connect the cable end to the brake lever, there are at least two steps for an operator; the operator needs to manually insert the connecting-pin into both the connecting-holes of the brake lever and the cable end and; needs to move the clip thereafter, which increases operational time.
<2> Also, simply installing the connecting-pin does not restrict the connecting-pin movement as both the connecting-holes of the brake lever and the cable end are at the insertion position or, that is, the connecting-pin movement is free before moving the clip.
<3> In addition, the operator needs to manually move the clip, and therefore there is a possibility of operational error, such as inappropriate pin insertion or insufficient clip movement, which makes it difficult to assure an accurate brake cable connection.
Especially, there is a problem when transporting the drum brake device while the brake lever and brake cable are connected because the connecting-pin can be disengaged from the brake lever during transportation, thereby releasing the cable end connection.